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Topic Review (Newest First)

10-29-2012 08:19 PM

shineboy

Quote:

Originally Posted by Kabigon

The mk3 Focus (and especially the ST) has a lot of electronics. Sometimes it is just the luck of the draw.

Hopefully, it's as simple as replacing the sensor.

Replaced 10/27... so far so good

10-29-2012 12:28 AM

Kabigon

Quote:

Originally Posted by shineboy

I hear you but dang less than 800 miles don't really expect any issues!

The mk3 Focus (and especially the ST) has a lot of electronics. Sometimes it is just the luck of the draw.

Hopefully, it's as simple as replacing the sensor.

10-28-2012 10:47 AM

shineboy

Quote:

Originally Posted by Kabigon

Think of the knock sensor as a microphone that is tuned to a specific frequency.
Even when the engine is running normally (no knocking/pinging), it has a certain amount of output.

If for example the knock sensor had no output while the engine is running, the PCM will see that as a bad sensor.

I hear you but dang less than 800 miles don't really expect any issues!

10-27-2012 03:21 PM

mikebontoft

this is true, that's all it is. you can trick or at least used to be able to trick a knock sensor to test its abilities by tapping on the block with the right tool.

10-27-2012 03:19 PM

Kabigon

Think of the knock sensor as a microphone that is tuned to a specific frequency.
Even when the engine is running normally (no knocking/pinging), it has a certain amount of output.

If for example the knock sensor had no output while the engine is running, the PCM will see that as a bad sensor.

10-27-2012 09:32 AM

shineboy

Quote:

Originally Posted by mikebontoft

knock sensor malfunction. I for some reason attributed it to the boost... lol.

It is weird, 2 out of 3 times I filled up with gas (93 octane) and the light comes on when I restart. I am in Ford service today and the the service guy told me that check engine light tend to be knock sensors or catalytic converters on Ecoboost....we will see

10-27-2012 09:28 AM

shineboy

Quote:

Originally Posted by Kabigon

The PCM still wants to know the intake air temp.

I agree... pretty sure it still has IAT sensor though

10-27-2012 01:14 AM

mikebontoft

knock sensor malfunction. I for some reason attributed it to the boost... lol.

10-27-2012 12:25 AM

Kabigon

Quote:

Originally Posted by scottso

If it doesn't have a MAF then what are the wires for that connect to the intake tube immediately after the air cleaner box?

The PCM still wants to know the intake air temp.

10-23-2012 09:25 PM

shineboy

Quote:

Originally Posted by Focus112

The ST doean't have a MAF??

Nope... 3 MAP sensors. Still did not like the idea of unfiltered air going in